Liquid-fuel burner.



D. E. & A. R. NHESS.

LIQUID FUEL BURNER.

APPLICATION man APR.8.19|a.

Patented Oct. 29, 12H8.

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DANIEL E. MIESS ANI) ALVYN R. MIESS, OF GLENDALE, CALIFORNIA.

LIQUID-FUEL BURNER.

Specification of Letters Patent.

Patented 9ct. 29, 19in.

To all whom it may concern:

Be it known that we, DANnsL E. MIEss and ALVYN R. Mines, citizens of the United States, both residing at Glendale, in the county of Los Angeles, State of California, have invented new and useful Improvements in Liquid-Fuel Burners, of which the following is a specification.

This invention relates to burners for liquid fuel, such as petroleum distillates and the like. It is an object of this invention to provide a burner which may have an effective means of initial generation and at the saine time act eiiciently as a self-generator after being once initially started. Difficulty has been found in providing an efficient, simple and reliable initial generating means for such a burneras is herein described; and this difficulty has been overcome by our invention which involves anew organization of parts, producing a new burner combination with several features of novelty. The various novel features, thevarious objects of the invention, and the manner in which these objects are obtained, will be best understood from the followingI description of a preferred specific forni of burner which embodies our invention.V

For the purpose of this detailed description reference'is had to the accompanying drawings in which-4 Figure 1 is a vertical section of our improved burner;

Fig. 2 is a vhorizontal section on line 2 2 of Fig. 1;

Fig. 3 is a horizontal section on line 3-3 of Fig. 1; v Y

Figa is a detail section on line Ll-f of Fig. 1; and 'j Fig. 5 is an enlarged detail section on line 5 of Fig. 1.

In most burners of the general class and character of the burner herein described the injection of the fuel gas or vapor into the mixing or combustion chambersvis in an upward direction. One of the features of our burner is the reversal of this arrangement, causing the lvapors to be injected downwardly into the mixing chambers. And from this feature there flow several very desirable results. In the drawings we show a burner in which the fuel nozzle 10 projects the vapors downwardly into the air chamber (or suction chamber) 11 and into the mixing tube 12 which extends downwardly and discharges at its lower end into a mixing chamber 13 from whence the mixed vapors and air pass under a downwardly depending baille wall 14 into a thin annular space 15 and thence through the perforated annular burner plate 16 to be burned in an annular flame surrounding the annular burner plate. The flame around the burner, with the heated gases of cornbustion rising from the flame, keep the nozzle at just thesuitable temperature for completely vapofiz-ing the fuel flowing through the retort 17 and flowing through the nozzle; but the heat is not sufficient to break down the fuel and cause its permanent gasification and deposit of carbon. lt is an object of this invention to provide a construction in which a uniform heat is applied to the parts in which the fuel is vaporized suflicient to cause perfect vaporization of the fuel but never of so high a temperature as to cause decomposition to any substantial extent.

It is also an object of this invention to provide a means for heating the fuel right to its point of discharge through the vapor nozzle. In previous burners of this general class it has been very diiicult to heat the fuel to its point of discharge; because usually this discharge has been located centrally under the burner where very little heat can reach it and where the cool incoming air usually passes directly over it and cools it to such an extent as to sometimes recondense the vapors to liquid form. rl`his cooling of the vapors renders it necessary to overheat them in the retort where they are vaporized, resulting at times in their permanent gasification and deposit of carbon and consequent clogging of the retort.

Our specific preferred form of burner now embodies a substantially cup-shaped annular burner base 2O having at its outer upper edge a small [fange 21 inside which the perforate annular burner plate, or screen,

`16 rests. This plate or screen is removable by removing the head 25 which holds it in place on base 20. Within the annular burner plate the base has an upwardly projecting' bathe ring or flange 22 inside the lower edge of the depending baffle ring or ange 14;. so that the mixed Avapors and air must pass upwardly over the edge of baffle 22 and then downwardly under the lower ledge of baffle 14 in order to'reach the annular space l5. Battle 14 depends from a head 25 which fits over the upper edge of burner plate 16. Head 25 carries the downwardly extending mixing tube 12 whose lower open end projects to a point in the cup-shaped base 20 somewhat above the bottom of that base, allowing suticient space between the end of themixing tube and the bottom of the base 20 for escape of the vapors and air.

Above head 25 there is a cap 30 whose edge rests upon the head 25; the cap being held to the head by a suitable screw 25. The cap forms an air chamber 1l over the head.' Fuel nozzle l0 discharges into the upper central part of this chamber l1 and directly downwardly through the chamber into mixing tube 12. Nozzle 10 is mounted in a member 31 removably fitted into a boss or sleeve 32 on cap 30. The various interengaging surfaces of the nozzle 10, member 51, cap 30, and head 25 are either machined after the parts are cast, or the castings are made from accurately machined patterns, so that lthe nozzle l0 is always accurately centered over the mixing tube 12. This is an important feature because it adds very 4greatly to the uniformity of mixture made in the burner. Retort tube 17 is screw-threaded transversely through member 31 and .is cappedat 33 on its outer end. And the tube is also brazed or otherwise sealed into the member 31 to make a tight joint. There is an annular groove 34 forming a passage around the retort tube and the retort tube has an opening 35 on its upper side through which the vapors emerge from the retort tube into passage 34, passing thence through passage 3G to the nozzle 10. This particular construction we find to be very eiicacious in preventing clogging of nozzle 10. WV e find that any small solid particles or deposits which would otherwise clog the nozzle 10, or partially clog it, and either stop or impair the operation of the burner, will .not pass upwardly out through the opening 35, but will remain in the end of retort tube 17. The end of retort tube 17 may be easily cleaned by the removal of cap 33. The retort tube is filled (preferably from end to end) with a filling of some material suitable to cause the minute subdivision of the liquid as it passes through the tube. We find that a filling of what is known as picture wire does very well. This wire is a braid of very tine wire; and we place say half a dozen or more of these braided wires in the tube,

villing the tube as tightly as possible. Liquid percolates through the interstices and is thus nely subdivided and most effectively uniformly exposed to the heat applied to the tube, and thus most effectively uniformly vaporized. Liquid fuel is fed into the retort at the end `designated 38 under a suitable pressure.

The retort and nozzle are removable. Member 31 removably fits in boss 32, so that the retort and nozzle may be easily lifted out at any time. The nozzle and retort are supported by this boss 32, the retort tube resting on the upper end of the boss.

Cap 30 has, preferably cast integrally therewith, a Vcircular flange 40 on its upper face which forms a small cup into which `a small amount of `the fuel liquid may be poured for purposes of initially heatin the retort. Also under the retort tube 3 we hang a small trough 4 1 into which a small quantity of liquid is poured for the same purpose. This trough performs not only the oice of a liquid holder but also the olice of a baffle or pretector for the retort tube when the burner is in normal operation. The cap and trough may each have an asbestos wicking 42 to absorb the oil and cause it to burn slowly and uniformly.

Air is supplied to air chamber 11 through a plurality of air tubes 45 which extend from the base 20 to the head 25, extending through both the base and the head. These tubes may be of any suitable number so as to be of the proper aggregate capacity to handle a sucient quantity of air. We preferably use four tubes of about roportionate size shown. The lowerencs of these tubes are welded or brazed into the burner base 20 and the upper ends are provided with washers 46 and nuts 47, which form airtight joints between the head 25 and the tubes, preventing leakage of air; and which also perform the office of holding the head 25 in place, thus holding the head, the annular burner platev 16, and the base 20 together. The tubes may be secured to base 20 in any manner that makes a tight joint.

Below the lower ends of air tubes 45 we provide a circular damper plate 48 supported upon a collar 49 set upon standard tube 50. This damper plate is revoluble, being provided with extension 51 to which a wire or rod may be connected; and is provided with damper openings 52 which may be registered partially or completely with the openings through tubes 45. In` normal operation of the burner this damper plate is arranged to allow free ingress .of air to the tubes; but during the starting of the burner the damper plate is turned so asto choke Yotl" the air to about one-fourth" its normal amount.n t

The supporting standard for the burner preferably comprises a hollow base 5,5 and a standard 50 which is preferably Inade of a tube or pipe screwed into the burner base 20. The lower end of thishojlloivstandard 50 is plugged at 5.6` with some kind vof a percus quence a small amount of liquid fuel will sometimes drop down through the nozzle into the burner base. This small amount of liquid fuel would interfere with the proper and normal operation of the burner if itstood in the base. Standard tube 50 is of sufficient capacity to hold any such amount of liquid fuel; and the interior bottom surface of the base may be made so as to slope slightly toward the tube 50 so as to drain all of this liquid into the tube. rIhe liquid having passed into the tube will slowly drain out through wicking 56 and into the base or ash pan of the stove or furnace in which the burneris installed. The wicking allows this liquid fuel to drain off and at the same time prevents any leakage of vapor out of the burner.

To start the burner a small amount of the liquid fuel (usually kerosene or a similar grade of4 petroleum distillate) is placed in the cup and trough 41 and ignited. The asbestos or other wicking 42 absorbs the liquid fuel and prevents it burning too fast when ignited. Whenthe retort tube and the nozzle members 31 have been suiiiciently heated, then the liquid fuel is admitted by manipulation of a valve on the fuel line leading to the retort end 38; and this fuel is immediately vaporized and the vapor projected downwardly under pressure through air chamber 11 and tube 12 into the lower mixing chamber 13. If any of the fuel is at `first not fully vaporized, it passes into standard tube 50 as explained. The air tubes i 45 are at first partially closed, to allow only a limited quantity of air to pass into air (or suction) chamber 11, and this air is drawn down by the vapor jet through mixing tube f l2 into mixing chamber 13, and thence along with the vapors over baille 22 and under baiie 14 and out through burner plate 16 to be ignited and burned. During its passage through the various chambers, etc., the air and vapors are very thoroughly mixed; so that when they reach the burner plate they are mixed so intimately that perfect, or very nearly perfect, combustion may then take place. As soon asthe burner is warmed up, the air openings are widened so as to allow ingress of the maximum or normal quantity of air. The flame then burns in a purplish blue color in an annular ring around the burner. The flame is maintained at a considerable distance from the burner plate, so that the burner plate is not directly exposed to the ame heat. The greatest temperature in the flame is of course in its middle or outer portions, in an annular ring around the burner. But the products of combustion and the heated air rising from the burner maintain a heated zone around the nozzle and around the inner end of the retort tube at just the right temperature to thoroughly, uniformly and continuously vaporize the liquid fuel without overheating it. Trough 41 protects the outer part of the retort tube so that the outer parts receive just the requisite amount of heat to thoroughly and uniformly vaporize the fuel without overheating. Thus, from the time the fuel enters the retort tube until it is discharged from the nozzle, itis subjected to a substantially uniform temperature (or perhaps somewhat gradually increasing temperature toward the nozzle) to cause its vaporization and to maintain that vapor up to the point of actual discharge. The point of discharge at the nozzle is substantially as hot or hotter than any other place in the vaporizing passage. This uniform temperature is maintained and not substantially overrcached even when the burner is operated continuously for long periods. Furthermore, if more fuel is admitted, in order to have a larger flame and deliver more heat, the arn rangement is such that the additional heat delivered to the retort tube and to the nozzle parts is substantially just sufiicient to offset the additional amount of fuel which must be vaporized, and cause vaporization without deposit of carbon. Of course, in the operation of the burner there may at times be some gasification of the fuel, so that both vapors and gases are made; and we donot limit ourselves to the exclusive use of vapors as distinguished from gases.

During the operation the whole burner becomes warm; and the air which enters through air tube 45 and passes through the various chambers and through mixing tube 12 and over and under the bailies, is warmed during its passage; as are also the vapors' so that the final thoroughly incorporatet mixture of air and vapor is discharged through the burner plate is pre-heated and is thus in condition for efficient combustion.

`Having described a preferred form of our invention, we claim l. A liquid fuel burner comprising a burner body having an outer perforated burner plate and a mixing chamber, a vapor nozzle centrally above the mixing chamber and discharging downwardly thereinto, and a fuel vaporizing retort above and to one sideof the burner body leading from one side of the burner body to and discharging into the, nozzle.

2. A liquid fuel burner comprising a circular burner body having an annular perforated burner plate and having a mixing chamber inside the body, a vapor nozzle 3rojecting vapor downwardly centrally om above into the mixing chamber, and la fuel vaporizing retort yabove and to one side ,of the burner body and leading :into and ,communicating with Ythe .nozzle from ,one side.

A ,liquid zfuel :burner compnising a `circular .bur-ner .body Ihaving lan :annular peritoratedfburner plate 4and having a mixing' chamber .inside the body,.a Vapor nozzle projecting vapor downwardly Ycentrally from above into 4:the mixing chamber, a ,fuel oorizing retort :above :and vto koneiside of the burner body ,and leading into ,and ,communicating -with `the Anozzle from lone side, and means n nder the outer ,portions `of the fretort :to ,protect .it lagainst ,the direct flame y of the iburner.

4. A liquidfuel burnercomprising a circular .burner body havino' lan ,annular perforated burner plate-anclhavingia mixing chamber insidethe body,a .vapor nozzle ,project-ing 'vapor downwardly centrally from above into the mxinglchambema fuel vaporizing .retort above iand Yto one side of [the burner .body .and leading into dand communicating withlthe nozzle lfrom oneside, and meansumderthe outerportions ofthe retort to ,protect it against thedirect flame ofthe burner, said `means `comprising -a ,trough suspended from the yretort and adaptedto hold-.a .suitable quantityaof liquid fuel tov-be ignitedfand `burnedei'or initially heating the retort.

5. `In .avburner oftheicharacter described, a bodyehaving akperforated burnerplate and a Tmixing chamber, means :for ,projecting a vaporous Jfuel 1 downwardly into the nii/Xing chamber, and meansat the lower'part off the mixing chamber for` draining oli' any ;liquid fueltherein embodying a draining opening anda stopper oi'porous, material adapted to allow,passage of kliquid but to1- prevent passage .digas or vapor.

6. .In arburner of the character described, ,albody having aA perforated. burner pl ate .and a mixing chamber, means 'for projecting `a vaporousfuel downwardly intothe mixing chambergand means at` the lower part of the Vmixingy chamber for l draining off l any liquid .fuel-therein, said means embodying a well communicating at its Vupper end kwith the lowerpart ,of thechamber and having at its Vlower end a,.por,ous stopper` adaptedtoallow. liquidto slowlyescape and adaptedto ,prevent egress ofvapors from the burner.

7. "In :a burner of the character described .wherein, a..vaporous `fuel is projected downwardlyintc'the burner, a. nozzle member having a verticalpassage, a nozzle at the lower end of said passage, and a retort tube extending c through ,saidJ member and lacross said passage, the -tube having an outlet ,openingatnts .upper .side toA allow vapors to pass ,upwardly out ofthe tube, and there beingia .passage leading around thel tube from the outlet opening `to the-[passage insaid' member.

S. Ina burner ,ofthe character described wherein a lvaporous iuel `is projected down` wardly into ithe burner, Ya `,nozzle Vmeinlfier ha ving ,a vertical passage ithereimla nozzle'at the lower end of said chamber, and atretort tube extending across the A,upperendbf ,the passage, the tube :hauing .an `outlet .opening ,at its upper side ato :allow wapcrs to pass upwardly .out ojf the tube, and t.there ,'beinga passage leading around the :tube jfromithe outlet to ithe ,vertical passage, the tube `pirojecting through and extending beyond ;the said Anozzle ;member.and .provided with a removable cap `on its .end for lcleaning purposes.

9. A burner of the character .-described, comprising' ,a V:body having an upper air chamber into Iwhich araporoils: fuel yis 'discharged centrally downwardly, 4a' .mixing tube ,extending downwardly vfrom .said air chamber, the body having a lower mixing chamber into ,which ithe lower ,fend ,of said mixing tube discharges, .a ,perforated burner plateflorming the outer wall ofsaidmixing chamberand Ineansrto su-pplyfl-airtoathe air chamber embodying Ytubes which extend verlicallyJthrough the mixingchamber and` discharge into Athe air chamber.

10. A burnerfof .the character described, comprising ay body `having an upper .air chamber into which `vaporous :fuel is .discharged centrally downwardly, `a mixing tube extending downwardly `from .said ,air chamber, ythe body .having ,a :lower `mixing chamber `into which fthe lower end fof ,said mixing tube discharges, aperforated burner plate forming the outer wall y of said mixing chamber, `and means to supplyairf t0 .the air chamber embodying tubes ,which ,extend vertically through the mixingf chamber `and discharge into the air chamberysaidmeans-for discharging la vaprous fuel downwardly into the air i chamber .l yembedying a downwardly 1 projecting'V nozzle member centrally ysitua-ted over theburneribodyand a substantia'lly horizontal fretorttube connecting with and discharging .into the nozzle member.

l1. A `burner -of i the character described, comprising a ,body :having an upper =`Vair chamber into which vaporous fuel Lis, discharged centrally downwardly, Aa mix-ing tube extending `downwardly "from said` air chamber, the body havingralower mixing chamber intovwhich-the lowergenjd Iof said A1nixin,c tube ldischarges, al perforated burner plate forming the onterwally of. saidfmixing chamber, means to supply air to the v air chamber embodying tubes ,whichV extend yertically through the mixing Chamber and discharge into. the fair chamber said means; for discharging a vaxjorous fuel downwardly into l the air cham A,er embosyieiigeli downwardly projecting `nozzle member centrally situated over the burner body, and a substantially horizontal retort tube connecting with and discharging into the nozzle member, a liquid fuel receiving cup on the burner body around the nozzle, and a protective baflie in the form of a trough adapted to receiveV liquid fuel for generative purposes under the retort tube.

12. A burner `of the character described, comprising a body having an upper air chamber into which vaporous fuel is discharged centrally downwardly, a mixing tube extending downwardly from said air chamber, the body having a lower mixing chamber into which the lower end of said mixing tube discharges, aperforated burner plate forming the outer wall of said mixing chamber, and means to supply air to the air chamber embodying tubes which extend vertically through the mixing chamber around the mixing tube and discharge into the air chamber; said means for discharging a vaporous fuel downwardly into the air cham` ber embodying a downwardly projecting nozzle member centrally situated over the burner body, and a substantiallyhorizontal retort tube connecting with and discharging Ainto the nozzle member; and a' protecting member suspended under the retort tube protected against direct flame.

13. A burner of the character described, comprising a burner body having a substantially cup-shaped burner base, an annular perforated burner plate mounted upon the outer edge of the burner base, a head mounted upon the upper edge of the burner plate;

said head and base and burner plate forming a mixing chamber, said head carrying a downwardly depending mixing tube open at both ends and discharging into the parts of said mixing chamber, an upper cap mounted upon the head and inclosing an air chamber over Vthe Vhead, a downwardly projecting nozzle centrally mountedin the upper part of the cap and adapted to project vaporous fuel centrallydownwardly through the air chamber and into and through the central Y mixing tube; and means to supply air to the air chamber. 1 j j 14. A burnerl of the character described, comprising a burner body having a substantially cup-shaped burner base, an annular perforated burner plate mounted upon the outer edge of the burner base, a head mounted upon the upper edge of the burner plate, said head and base and burner plate forming a mixing chamber` saidv head carrying a downwardly depending mixing tube open `at both ends and discharging into the lower part of saidmixing chamber, an upper cap mounted upon the head and inclosing an air chamber overthe head, a downwardly projecting nozzle centrally mounted in the' uptially cup-shaped burner base, an annular perforated burner plate mounted upon the outer edge of the burner base, a head mounted upon the upper edge `of the burner plate, said head and base and burner plate forming a mixing chamber, said head carrying a downwardly depending mixing tube open at both ends and discharging into the lower parts of said mixing chamber, an upper cap mounted upon the head and inclosing an air chamber over the head, a downwardly projecting nozzle centrally mounted in the upper part of the cap and adapted to pro- `ject vaporous fuel centrally downwardly through the air chamber and into and through the central mixing tube; means to 'supply air to the air chamber; the interior surface of said burner base sloping somewhat toward the center, a liquid .well communicating at its upper end with the center of the base and adapted to receive and temporarily hold any excess of liquid, and a `porous plug for the lower end of said well adapted to slowly pass any accumulated liquid, and adapted to prevent any egress of vapors from the burner.

16. A burner of the character described, comprising a burner body having a substantially cup-shaped burner base, an annular perforated burner plate mounted upon the outer edge of the burner base, a head mounted upon the upper edge of the burner plate, said head and base and burner plate forming a mixing chamber, said head carrying a downwardly depending mixing tube open at both ends and discharging .into the lower part of said mixing chamber, an upper cap mounted upon the head and inclosing an air chamber over the head, a downwardly projecting nozzle centrally mounted in the upper part of the cap and adapted to project vaporous fuel centrally downwardly through the air chamber and into and through the central mixing tube; meansto supply air to the air chamber, said means comprising a plurality of air tubes extending through the burner base and open at the lower ends to atmosphere and extending upwardly through the mixing chamber and through the `head' and discharging air into the air chamber; said head having a depending an.-

nular baiie-iiange close to the annular. burner plate to form a thin annular space between the flange and plate, and under which baille .the vapors and' air must pass in order to reach. the burner plate, and saidr burner base having an upwardly projecting `baille flange inside the lower edge of the depending baiile flange and over which last mentioned baffle flange the vaporsand air must pass.,

117. A burner of the character described, comprising a burner body having a substantially cup-shaped burner base, an annular perforatedV burner plate mounted upon the outer edge ofthe burner base, a head mounteduponthe upper edge ofthe burner plate, said head and base and burner plate forming a` mixing chamber, said head carrying a downwardly depending mixing tube open at bothends and discharging into the lower part of said mixing chamber, an upper cap mounted upon the head and inclosing an air chamber over the head, a downwardly projecting nozzle centrally mounted in the upper part' of the cap and adapted to project vaporous fuel centrallv downwardly through i the air chamber and into and through the central mixing tube; a horizontal retort tube connected at its inner end with the4 nozzle and extending outwardly, a liquid receiving cup on the top of the burner cap, a protective baille and liquid receiving trough under the retort tube; means to supply air to the air chamber, said means comprising a plurality of airtubes extending through the burner base and open at the lower ends to atmosphere and extending upwardly through the mixing chamber and through the head and discharging air into the upper mixing chamber; said'head having a depending annular baiiie flange close to the annular burner plate to form a thin annular space between the flange and plate, and under which baffle flange the vapors and air must pass in order to reach the burner plate, and said burner base having an upwardlyprojecting baiile lia-nge inside the lower edge of the depending baffle iiange and over which last mentioned bailie flange the vapors and air must ass. p 18. A liquid fuel burner comprising a circular burner body having an annular perforated burner plate and having a mixing chamber inside the body, a vapor nozzle projecting vvapor downwardly from above into the mixing chamber, a fuel vaporizing retort above the burner body and communieating with the nozzle, and a liquid fuel cup upon the upper part of the burner surrounding the fuel nozzle and adapted to hold a small quantity of liquid fuel for initial generation purposes.

19. A liquid fuel burner comprising a circular burner body having an annular perforated burner plate and having a mixing chamber inside the body a vaporV nozzle projecting vapor downward-ly from above into the mixing chamber, a fuel vap'orizing retort above the burner body and communieating withthe nozzle, a liquid fuel cup upon the upper part of ther burner surrounding the fuel nozzle and'adapted to hold a small quantity of liquid fuel for initial generation, and a protective baille and liquid fuel: receiving trough under the retort tube.

of the. burner, and an air control damper mounted on the lower side ofthe burner and adapted to control the tubeopenings.`

21. A burner of the character described, comprising a burner body having -a substantially cup-shaped burner base, an annular perforated burner plate mounted ,upon the outer edge of the burner base, a head mounted upon the upper edge of the burner plate, i

said head and base andburner` plate forming a mixing chamber, a downwardly dependingmixing tube open at both ends and discharginginto the lower part of said mixing` chamber, an upper' cap mounted upon the ead andinclosin `an air chamber over thehead, a` downwar 1y projecting nozzle centrally mounted in the upper part of the cap and adapted to'project vaporous fuel centrally downwardly through the air chamber and into and through the central mixing tube; and means to supply air to the air chamber, said means comprising a plurality of airtubes extending through the burner baseand open at'the endsto atmosphere andextendin upwardly through the lower mixing chamher andthrough the head.l and discharging air into the air chamber, said tubes being afiixed to both the base and head to hold the burnerparts together.

22. In a burner of the class described, a burner base and a burner head and ap-la-te between them forminga chamber, a cap over the head forming another chamber, and air tubes extending through the base and head and affixed thereto to hold the burner parts together. c

23. A burner-of the character described, comprising a body having an air chamber at one end into and through which vaporous fuel is projected substantially centrally, a

saidhead carrying mixing tube extending from the air chem- In Witness that we elaim the foregoing We ber, the body having a mixing chamber lnto have hereunto subscribed our names this 3d 104 Which the mixing tlbe dischlrges, e pei dey of April, 1918. orated burner plate orming t e outer Wa 5 of the mixing chamber, and air tubes ex- DANIEL E' MIESS tending through the mixing chamber and ALVYN RWESS discharging into the air chamber to supply Witness: air to that chamber. VIRGINLA I. BERINGER.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Entente. Washington, D. C. 

